1. Field of the Invention
The present invention pertains to downhole tools typically used in the development of oil and gas wells for providing an annular seal and/or anchoring means between one conduit disposed in another and, in particular, the present invention pertains to a combination shear type and rotational type release mechanism for such tools.
2. Background Art
In the art of downhole tools used in the well drilling industry of the type which provide for a seal to be established in the annulus between one conduit and another in the well bore it is preferred to design such tools to have an inner elongated tubular member, sometimes referred to as the mandrel, on which are mounted sealing and anchoring mechanisms which are operated to be set in and released from the working position by effecting relative axial movement between the mandrel and the mechanism components disposed therearound. One specific type of tool of the general type discussed herein is known as a packer. Many applications of well packers require that the packer be retrieved from the well after serving its purpose or for performing certain operations on the well. In this regard it is usually necessary to effect relative axial movement between the mandrel and the associated components in a direction opposite to that which resulted in setting of the packer. To this end a number of different release mechanisms have been developed which require specific mechanical operations to be performed from the surface or by mechanisms disposed in the tubing string to which the packer is connected. For example, packer release mechanisms are known which require the exertion of an axial force on the tubing string, or rotation of the tubing string to effect operation of the release mechanism.
It has been determined that it is highly desirable in the application of well packers and the like that the option be available to the equipment operator to effect release of the packer from the set position by more than one type of releasing action. In this regard the present invention has been developed to meet a long felt need for a combination releasing mechanism for well packers and the like which is economical to manufacture and is reliable in operation. Moreover, the combination release mechanism of the present invention provides for releasing a well packer or the like from a set position by one of two relatively simple mechanical operations which can be effected by basically fundamental and easily accomplished movements of the packer mandrel.